I replaced the OEM fork springs at about 78,000 miles, 110,000 km in 2007 .
I used Progressive brand progressive springs brought the front up a bit, forks stopped bottoming out handling may have improved but I usually only ride the bike to work ,no twisting roads anywhere near me just city riding .
One thing I did notice, is leaving home, I have to go down a curb out of my driveway and I get a slight squeak not noticeable when riding .